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    Haber Process. Right. It's basically manufacturing ammonia; nitrogen (fractional distillation of air) and hydrogen (reaction between methane and steam) make ammonia, using hot iron catalyst. Ammonia is liquified and removed while excess N and H is recycled.

    200 atmospheres is used as it is a compromise. A high pressure would be more expensive to build a station, but a high pressure is needed for high yield because it favours the forward reaction (as it produces less molecules, 4-->2).

    450ºC is used as a compromise also. A high temperature is needed for a fast rate of reaction & for catalyst to work, but a low temp is needed for high yield because it favours forward exothermic reaction.

    How is nitric acid made?
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    Ammonia and oxygen are passed over a hot platinum catalyst to form nitrogen monoxide which is cooled down and water and oxygen are added to from nitric acid.

    What are the advantages and disadvantages of using instrumental techniques to identify elements and compounds?
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    advantages - doesnt use sample, is quick, accurate as to the specific ions
    disadvantages - machines usually large, expensive, need to be trained to use them

    What are the properties of transition metals?
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    (Original post by Excalibur)

    What is a base?
    It is a proton remover ie it removes H+ ions from solution . . . according to the ideas of bronsted and lowry, there is also something about arrhenius . . . i cant remember! think i might need to revise this :confused:

    Okay . . . another qn: Describe how steel is made with reference to redox reactions and acid-base reactions.
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    -Coloured compounds
    -good catalysts
    -high tensile strength
    -high melting/boiling points
    - high density
    -solid at room temps except mercury
    um....wat else? have i missed anything?

    i had to think a little about this one so ill ask!
    why does sodium have a lower melting point than lithium? (Na-11, Li-3)?

    EDIT: oh sos i didnt see ur Q n A. um...i thought it was a proton acceptor? absorbs hydronium ions and releases hydroxide ones? i think neway.
    and i have no ideas about steel manufacturing. hope we dont need that 4 edexcel double award.
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    (Original post by tim 45)

    What are the properties of transition metals?
    Sorry, posted another qn without yours being answered! right, transition metals:
    1. form coloured compounds
    2. good conductors of heat/electricity
    3. malleable
    4. hard and tough
    5. high densities
    6. higher melting points than other metals (apart from mercury)
    7. less reactive than other metals
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    Why does sodium have a lower melting point than lithium? (Na-11, Li-3)?

    That's AS.... it's something to do with the atoms being bigger, so the delocalised electrons are further apart from the metal ions, so the attractive force is reduced & is a weaker structure.

    Describe how crude oil is separated.
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    by fractional distillation in an oil refinery, each fraction boiles within a different temperature range. Lower boiling point fractions condense higher in the column.
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    which equations do we need to learn off by heart, do we need to know the blast furnace ones?
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    (Original post by Excalibur)
    Why does sodium have a lower melting point than lithium? (Na-11, Li-3)?

    That's AS.... it's something to do with the atoms being bigger, so the delocalised electrons are further apart from the metal ions, so the attractive force is reduced & is a weaker structure.

    yeh...basically! the ionisation energy required is lower caus the electron in outermost shell is further away. it isnt AS...found it in a past paper!

    um ...no questions? i cant think of any.....
    k simple....TEST FOR SATURATED/UNSATURATED HYDROCARBONS.

    EDIT: they dont usually ask for entire equations ...hardly ever really....but ud be better off knowing some basic 'what hapens' in a blast furnace....i stil need to do that..lol.
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    Depends on board & whether you do triple or double. For Double Award AQA, no you don't.

    Add yellow-brown bromine water, if it's unsaturated it turns colourless.

    Another question: describe how copper is purifyed by electrolysis.
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    aw man...thats 2 long! urm ok
    ANODE: impure copper
    CATHODE: small pure copper

    copper looses electrons (oxidation) to fprm cations which travel through a copper sulphate (usually) electrolyte..attracted to the cathode and then gain electrons (reduces) to form copper which plates the pure copper anode.

    describe polymerisation of ethene.
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    Copper is purified by using a lump of impure copper as the anode and a small rod of pure copper as the cathode. basically, the electrons are pulled of the anode, causeing the Cu2+ ions in the impure copper to go into solution (the impurities fall to the bottom). The Cu2+ ions are then attracted to the cathode, where they gain 2 electrons to become copper metal, and bind with the cathode itself. After some time, the cathode can be removed and it will be much larger than before; thus the copper is purified.

    Q: What is the name of the industrial equipment used when calcium carbonate is thermally decomposed to produce quicklime (CaO) and carbon dioxide on a large scale??
    (btw I have no idea of the answer but it is a question in my textbook (OCR specific), although I can't actually find the answer anywhere!!)
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    Uhh.. many monomers (ethenes) join together to form a long chain polymer, (poly)ethene. Used for plastic bags and bottles too :p:

    I have no idea about the quicklime one. A kiln? :p:

    How do sedimentary rocks form? Why do they sometimes have ripple marks? Why are they often find tilted/folded/faulted/upside down etc?
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    aw this is confusing caus lots of ppl are doin this!!! hehe. gud tho.

    sedimentary rocks form when sediments from erosion etc. settle at the bottom of sea beds and are compressed by following sediment which then causes it to compress. the sediments may contain dead plants/animals leading to fossil formation. Ripple marks are due to the pressure and heat from the earths mantle causing rock to fold and compress etc.

    i duno about the quicklime thing either.

    name uses of all halogen gases

    btw....isnt **** quicklime???? from the blast furnace? or am i just demented.
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    Excalibur was right, when calcium cardbonate is heated in a kiln, it decomposes to calcium oxide (quicklime) and CO2.
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    Chlorine is used to kill germs in swimming baths and drinking water. Iodine is used to develop finger prints as it dissloves in skin oils. Not sure on any others.
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    (Original post by Krystal)
    aw this is confusing caus lots of ppl are doin this!!! hehe. gud tho.

    sedimentary rocks form when sediments from erosion etc. settle at the bottom of sea beds and are compressed by following sediment which then causes it to compress. the sediments may contain dead plants/animals leading to fossil formation. Ripple marks are due to the pressure and heat from the earths mantle causing rock to fold and compress etc.

    i duno about the quicklime thing either.

    name uses of all halogen gases

    btw....isnt **** quicklime???? from the blast furnace? or am i just demented.
    Yes you're demented :p: Just kidding! Quicklime is Calcium carbonate, while **** is calcium carbonate reacted with impurities in iron ore (silicon dioxide).

    Halogen gases:
    - Chlorine: disinfectant, bleach, polymer PVC, kill bacteria in water/pools, hydrochloric acid
    - Fluorine: toothpaste
    - Iodine: antiseptic
    - Silver halides used in photographic film/radioactive film


    Describe how the atmosphere today is different from the first billion years of the Earths history.
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    Silver halides can also be used in photo film and paper and in xrays. Hydrogen halides dissilve in water to produce acidic solutions. Chlorine can also be used to produce hydrochloric acid, dininfectant bleach and plastics.

    Q1. What effect does the temperature have on a reaction between an acid and a salt and why?
    Q2. (for seperate science) Name the colours formed when you put lithium, sodium, potassium, calcium, and barium into the flame of a bunsen burner and name the wire which is used to hold the compound and how it is cleaned?
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    For the first one billion years, the earth atmospher was mainly co2 and steam with some methane, however plants evolved and took away much of the co2 and converted it to oxgyen. Methane broke down to form nitrogen gas and the atmosphere now is mainly 80% nitrogen and 20% oxygen.
 
 
 

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